The present invention relates to a brake apparatus for a vehicle, and more particularly to the apparatus provided with a regenerative braking device and a hydraulic pressure braking control device, to achieve a regenerative braking cooperative control.
In general, as for a brake apparatus for use in a hybrid vehicle having an engine and an electric motor, the regenerative braking device and hydraulic pressure braking control device are provided to achieve the regenerative braking cooperative control. For example, Japanese Patent Laid-open Publication No. 2000-219114 discloses a brake-by-wire type service brake for vehicles such as an electric vehicle or hybrid electric vehicle, having a regenerative braking system for collecting brake energy by means of a DC motor used for a generator, and a hydraulic brake system actuated by hydraulic pressure discharged from a hydraulic pressure pump, to improve a feeling of operation of a brake pedal. In the Publication, it is described that a master cylinder is not operated by the brake pedal at a normal reduced speed range of the vehicle with the brake pedal being depressed, whereas the master cylinder is operated by the brake pedal at a highly reduced speed range of the vehicle with the brake pedal being largely depressed, to increase the hydraulic pressure.
According to the brake apparatus as disclosed in the aforementioned Publication, the hydraulic pressure pump can be controlled to supply the hydraulic pressure according to an amount of operation of a manually operated braking member into wheel brake cylinders, when a stroke of the manually operated braking member is equal to or smaller than a predetermined stroke. However, the brake apparatus has been constituted such that the hydraulic pressure will not be supplied into the wheel brake cylinders, in such a range that the stroke of the manually operated braking member is equal to or smaller than the predetermined stroke. Therefore, if the manually operated braking member is rapidly operated in that range, the regenerative braking device or the hydraulic pressure pump may be delayed in operation, whereby an unusual feeling might be given to a vehicle driver.